Neville alexander thomas ntx feary



N. A. T. N. FEARY.

FABRlC FOR AIRCRAFT AND PROCESS OF MAKING SAME.

APPLICATION FILED APR.2I, 191 9.

Patented J an. 13, 1920.

mars s'riirs ye. BEIGE.

NEVILLE ALEXANDER THOMAS NIX FEARY, OF PETERBORQUGH, ENGLAND.

FABRIC FOB, AIRCRAFT AND PROCESS OF MAKING SAME.

memos.

Application filed April 21, 1919.

To all whom it may concern:

Be it known that I, NEVILLE ALEXANDER 'irroiriis NIX FEARY, a subject of the King of Great Britain, residing at No. 1 Fletton avenue, Peterborough, in the county of Northants, England, have invented certain new and useful Improvements in or Relating to Fabrics for Aircraft and Processes of Making Same, of which the following is a specification.

The present invention relates to fabrics used for covering the wings or planes of aircraft and for purposes for which aeroplane fabric is used and similar purposes and its main object is to produce a fabric that in comparison with its weight shall be stronger and less liable to expansion or contraction than fabrics for the said purpose as heretofore known.

According to the said invention fabrics for the purposes aforesaid are partly or essentially composed of cork and this is preferably efiected or carried out by the use in the composition of the fabric of fragments of cork, wire in an interlaced or woven form, flexible covering material such as paper and a binding medium such as a solution of casein.

The paper used should be thin and light although strong such as the finest tissue paper made from rags and commonly referred to as thin rag paper.

A suitable binding medium consists of a solution of casein in water with horror, water glass (solution of sodium or potassium silicate) and tannic acid and suitable proportions of these substances are to one ounce avoirdupois of casein, three twentieths of an ounce avoirdupois of borax, seven fluid ounces, (British measure of capacity) of water, half an ounce avoirdupois of water glass of commercial strength and one hundredth to three hundredths of an ounce avoirdupois of commercial tannic acid in powder. The borax is first mixed with the casein and the two dissolved with heat in the water. The water glass and tannic acid are then added and mixed in successively in that order. The boraX is used to enable the casein to dissolve in the water, the water glass is used to impart strength and waterproof quality to the binding medium and the tannic acid is used to improve the adhesive and waterproof qualities. It is preferred to use a small proportion of formaldehyde with the Specification of Letters Patent.

Patented Jan. 13, 1920.

Serial No. 291,583.

said solution in the form of a solution of formaldehyde in the proportions of eight fluid drains of formaldehyde of 40 per cent. strength to ten fluid ounces of water, or preferably ten fluid ounces of a five per cent. solution of casein in water. of formaldehyde improves the waterproof quality of the binding medium and paper or the like and is preferably used in conjunction with the binding medium in the manner hereinafter described.

The wire employed should be of steel in an interlaced or woven form. The gage of wire suitable is 37 S. WV. G. (.1727 m. m. diai'neter) and the meshes may suitably be about eleven to thelineal inch.

The components of the fabric are preferably brought together and combined in the following manner.

One side of one sheet of the paper has applied to it by brushing or in any other convenient way, the binding medium and is then applied to one side of the interlaced or woven wire. Cork in fine fragments or dust is then sprinkled or dusted over the exposed wire and binding medium. One side of another sheet of the paper has sprinkled lightly over it the solution of formaldehyde and is then applied to the exposed wire, cork fragments and binding medium and the whole subjected to moderate pressure whereby the two sheets of paper are pressed onto the wire and the cork and binding medium caused to be squeezed together in the interstices in the interlaced or woven wire between the two sheets of paper so that the said interstices contain a cork composition consisting of cork and a binding medium. The binding medium not only causes the fragments of cork to adhere together but also to adhere to the paper and wire and causes the paper to adhere to the wire. When the fabric is dry, that is, when the binding medium has set, dried or hardened and the components of the fabric are thus firmly secured together it is placed in boiled linseed oil, oil varnish or oil varnish diluted with driers or the like in a. pressure chamber and subjected to air pressure of say fifty pounds to the square inch so as to force the oil or the like into the fabric. After this has been done and the fabric is again dry it should be coated or covered with a suitable preservative or waterproofing material or composition preferably oil This solution surface of rigid material on the one side and a surface of resilient material on the other side such as a rubber covered roller or a rubber band or belt.- By this means the fabric is given a comparatively flat surface on that side to which the pressure is applied through the medium of a rigid surface as the paper on that side is not caused to be depressed to any substantial extent into the interstices between the wires, and this side would in use of the fabric be generally considered to be the outer face or right side. On the other side as the pressure is applied to it through the medium of a resilient material the paper on that side is depressed into the said interstices and squeezes the cork and binding medium together therein.

In the drawing Figure 1 is a section through the fabric; Fig. 2 is diagram of the machine; Fig. 3 is a section through the hopper; and Fig. 4; is a diagram of a modified form of the machine.

Fig. l of the accompanying drawings illustrates in section. to an enlarged scale and in an exaggerated manner a fragment of fabric made according to the said invention in the particular manner hereinbefore described, a being the interlaced or woven steel wire 7), b the inclosing layers of rag paper and 0 the cork composition between the paper and the wires. The paper 6 is that to which pressure. has been applied through the medium of a resilient material and it will be observed that this paper is depressed into the interstices between the wires.

' hen comparatively small sheets of the fabric are to be produced say not larger than about five or six feet each way they may be made by hand on a table by first placing thereon a sheet of the-paper, brushing the binding medium on it applying to it the woven wire and then sprinkling on the fragments of cork. The other sheet of paper after being sprinkled on one side with the solution of formaldehyde is applied to the exposed wire and cork fragments and binding medium with its wet face innermost. Pressure is then applied by means of a hand, roller covered with soft india rubber of good quality care being taken to use the roller progressively from one edge to avoid the formation of air bubbles. When this has been done the compounded sheet may be slid onto another part of the table or to another "flat surface until the binding mej dium'has set dried or hardened so that the press one on the other.

sheet may be handled freely. The whole operation should be conducted in a warm atmosphere and the drying or setting of the binding medium is preferably facilitated by subjecting the sheet to a temperature of say 100 to 120 Fah.

The hand production of the fabric as described is comparatively slow and is still less convenient when substantially continu-v ous or comparatively large or long sheets of the fabric are to be produced. In order therefore to facilitate manufacture of the fabric it is preferred to employ machine or apparatus to which the paper and woven wire are continuously fed and in which they are brought together and caused to pass between rolls for applying the pressure to the components. Such an apparatus is illustrated diagrammatically in Fig. 2 in which (Z is a fixed table over which an endless belt, band or sheet 0 of woven wire fabric is caused to travel by rotation of the rollers c, e over which. it passes and it is kept in a taut condition by a weighted loose jockey pulley e. The paper 6 is fed from a roll 7 and caused to travel over the table by the action of the band 6. The interlaced or voven wire a is fed from a roll a passes over a roll 6& in close proximity to the table a? and so caused to travel with the paper I)" ent operative face it should be of soft india rubber of good quality without any canvas backing or the like. Around the rolls 72,, h" there is an endless band, belt or sheet of woven wire fabric The bearings for the rolls b h are provided with springs so that the tendency of the rolls is to resiliently k is a tunnel into which the fabric passes after leaving the rolls 71. h which tunnel is maintained at a temperature of say 120 Fah. by gas jets 7c impinging on a metal plateJe above which the fabric passes but without touching the said plate. The casein solution is brushed over the upper face of the paper 5 as it travels from the roll f to the roller 01. or it might be applied by a duct or roller fed from a supply a fixed knife edge being pro ided against the surface of the roller at its rear to prevent the paper unduly adhering. The band a carries the paper 6 along and at the roller a the woven wire a comes closely in contact with it. As the paper Z and woven wire a pass under the hopper 9 fragments of cork 0 fall onto and mix with the casein solution on the paper and about the wires of the woven wire a. As the paper I) and woven wire a with the cork composition consisting of cork and casein solution pass between the rolls h it the other paper I) which is being fed from the roll 7"- and passes around the roll it outside the woven wire band j, is met and by the action of the rolls h, h the whole of the components are squeezed together. The upper surface of the paper Z) between the rolls f and Zr is sprayed with the solution of formaldehyde and this is the face of the paper which is presented to the other components of the fabric. The squeezing action takes place through the medium of the woven wire band 7' on the upper side and the rubber band i on the lower side. The band j at the part where the squeezing action takes place forms a non-flexible surface against which the pressure of the rubber band 2' acts with the result that while the paper 6 remains fiat the rubber forces the paper 6 into close contact at practically all parts of the uneven surface of the woven wire a and into the interstices therein against the resistance of the cork and casein solution binding medium until the papers I), Z) and the cork and binding medium are closely squeezed together the solution of formaldeiyde penetrating the mass. After leaving the rolls h h the partially made fabric passes into and through the tunnel above the hot plate k onto the roll Z whereby the components of the fabric are caused to dry together in close cohesion so that by the time the fabric leaves the tunnel is the fabric may be safely handled, and impregnated with oil or the like and subsequently varnished as before described.

In the machine described the components of the fabric are subject to only one squeezing action and that a cold one. Where more cork is used in the fabric than hereinbefore indicated as for instance when the cork is sufficient to cover the reinforcement then it is preferred to subject the partially made fabric to further squeezing actions under heat. A modified form of the machine shown in Fig. 2 in order to effect this is diagrammatically illustrated in. Fig. 4:. In this machine three more squeezing pairs of rolls A 7&3 are provided so that the partially made fabric passes successively between four pair of rolls. The band j passes over all the rolls 72, 1 2, h and the band i similarly passes over all the rolls 72. 72- h The rolls h 72. are steam heated in the usual way to a temperature of 212 Fah. or 212 to 24.0" Fah. and the bearings for the rolls if, 77. are provided with springs similarly to the rolls it", h and the several springs are so adjusted that the pressure between the rolls gradually increases from the entry pair to the delivery pair. The rolls are also all geared together so as to rotate at the same peripheral speed. With this machine further heating of the fabric after leaving LllQ rolls may usually be dispensed with as by the time it leaves the last pair of rolls it should be sufliciently dry to be impregnated with oil or the like as hereinbefore de cribed.

The cork dust is preferably such that it will pass through woven wire of gage 37 S. lV. G. .1727 m. m. diameter) having forty meshes to the lineal inch and the bottom of the hopper is provided with a woven wire sieve so made. Fig. 3 illustrates in section a part of the bottom of the said hopper gin which 9 is the sieve bottom. in order to facilitate the passage of the cork dust through the sieve 9 another similar but reciprocatory sieve g is provided face to face with it and this sieve is reciprocated by mechanical means, that may be put out of action when not needed. The sieve 9 also prevents fall of cork dust when not needed as when it is stationary it blocks the passages through the sieve g sufhciently to prevent passage of any material quantity of cork therethrough although there may be some little vibration caused by parts of the machinery still running.

The bands 0, j are preferably of phosphor bronze wire having a .Q'age of 35 S. W. (.2031 m. m. diameter) and about 30 to meshes to the lineal inch.

The machines described are preferably run at about eighty feet per hour.

No very great care need be exercised as to the quantity of casein solution applied to the paper 6 as some superfluity of it will not be prejudicial and will to some extent be squeezed out and a little unevenness in the coating will be rectified by the squeezing action.

Sufficient of the casein solution will usually be available to bind the cork and to secure all the components of the fabric together by brushing it on the paper.

It is generally preferred that as much cork be used as the limit of weight for the fabric will admit of and where the woven wire a can be made of lighter wire than 37 S. W. G. sufficient cork may be used to cover the Wire entirely next the paper I). On the other hand apart from the factor of weight cork must not be used in such quantity that the cork composition will'crack on bending the fabric as may be necessary for any particular purpose. If flat or even semi-circular steel wire be available for the woven wire material a it may be embedded in the cork without making the fabric unduly thick. This may be done by providing an additional cork hopper to discharge cork onto the casein solution on the paper 7) before it reaches the roller a It is not essential that a casein solution be used as a binding medium and adhesive as other compositions may be suitable but the medium and adhesive should when dry be waterproof and also non-inflammable and the casein solution before described'is such.

What I claim and desire to secure by Letters Patent of the United States is l. A fabric for the purposes set forth consisting essentially of wire fabric, paper on each side of it and a cork composition in. the spaces between the Wire fabric and between the sheets of paper.

2. A fabric for the purposes forth comprising cork, impegnated with oil, oil Yurnish or the like under pressure.

8. A fabric for the purposes set forth comprising cork and wire fabric, impregnated with oil, oil varnish or the like under pressure.

4-. A fabric for the purposes set forth consisting essentially of cork, Wire fabric and paper or the like, and a binding; medium or adhesive, and impregnated ith oil, oil varnish or the like under pressure.

5. A fabric for the purposes set forth consisting essentially of Wire fabric, paper on each side of it, and a cork composition in the spaces between the wire fabric, andbetween the sheets of paper, and impregnated with oil, oil varnish or the like under pressure.

6. A, process for making a fabric for the purposes set forth consisting essentially in applying a binding medium to paper applying it to one side of interlaced or wove-n wire, applying fragments of cork thereto and then applying other paper to the other side of the interlaced or woven wire and cork and pressing the whole together.

7. A process for making a fabric for the purposes set forth consisting essentially in squeezing together fragments of cork with a binding medium, wire fabric and paper by and between a surface of rigid n'iaterial, and

surface of resilient ma erial.

8. A process for making a fabric for the purposes set forth, consisting essentially in squeezing together fragments of cork with a binding medium, wire fabric and paper by and between heated rolls.

9. A process for making a fabric for the purposes set forth, consisting essentially in squeezing together fragments of cork with a binding medium, wire fabric and paper, and impregnating the combined materials with oil, oil varnish or the like, under pressure.

NEVILLE ALEXANDER THOMAS NIX FEARY. 

